Bottom Line:
At the same time, in vivo confocal microscopy revealed endothelial cells in the rounded dark areas, acellular hyporeflective layers on the Descemet's membrane, and hyperreflective linear lesions.The abnormal findings only existed at the Descemet's membrane and corneal endothelial layer.Previous reports dealing with posterior polymorphous dystrophy (PPMD) examined using in vivo confocal microscopy reported almost the same findings, suggesting that PCV and PPMD may be the same at the microstructural level.

Affiliation: Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan. ryo-w@oph.med.tohoku.ac.jp

ABSTRACTThe histopathology of posterior corneal vesicles (PCV) has not yet been revealed. A 15-year-old girl, who was diagnosed by slit-lamp microscopy as PCV, was examined using specular microscopy, in vivo confocal microscopy, and anterior segment OCT (optical coherence tomography). Anterior segment OCT showed that the thickness of both corneas was within normal limits. At the same time, in vivo confocal microscopy revealed endothelial cells in the rounded dark areas, acellular hyporeflective layers on the Descemet's membrane, and hyperreflective linear lesions. These findings were not reported previously by slit-lamp and specular microscopy. The abnormal findings only existed at the Descemet's membrane and corneal endothelial layer. Previous reports dealing with posterior polymorphous dystrophy (PPMD) examined using in vivo confocal microscopy reported almost the same findings, suggesting that PCV and PPMD may be the same at the microstructural level.

f3-opth-4-1243: A) In vivo confocal microscopy showed that the left corneal endothelial cell showed the normal appearance. B) The image was captured obliquely and showed no abnormality of keratocytes in the adjacent corneal stroma to the endothelium.

Mentions:
A 15-year-old girl was referred to the Tohoku University General Hospital because of a suspicion of corneal dystrophy. On the right eye, slit-lamp examination revealed a horizontal band-shaped structure which contained small vesicles (Figure 1A, C). The left eye was entirely normal (Figure 1B, D). Her mother’s cornea had no abnormal f indings. Specular microscope (Konan Noncon Specular microscope SP9000; Konan Medical, Inc., Hyogo, Japan) showed that the density of the corneal endothelium and the coefficient of variation were 1331, 1060, 1275 cells/mm2 and 0.36, 0.67, 0.35 at the superior, middle, inferior section, respectively. At the middle area, the shape of the cell was irregular and some parts contained dark areas and bright spots inside the endothelium. In contrast, in the left eye, the density of the central corneal endothelium and coefficient of variation were 2941 cells/mm2 and 0.33, and there were no abnormal findings. The patient was diagnosed as PCV. HRTII-RCM revealed that three different layers were clearly separated in the epithelial layer (superficial, wing, and basal cell layer) on the right eye and suggested that the patient had well-differentiated epithelial cells. In the subbasal nerve plexus layer, the number, bifurcation, and thickness of the nerves showed similar appearance (Figure 2A) to the left eye (Figure 2B), and no inflammatory cells were detected. In the substrate layer, we detected the normal number of keratocytes and neither Langerhans cells nor round leukocytes were detected, suggesting no inflammatory response in the stromal layer. Furthermore, close to the Descemet’s membrane, the cell appearance and the number of the posterior stromal cells look normal (Figure 2C, D). In the Descemet’s membrane layer, an acellular hyporeflective layer (Figure 2E, black arrows) and a hyperreflective linear lesion (Figure 2E, white arrows) were clearly detected (Figure 2E) because of winding the Descemet’s membrane. In the endothelial layer, the various sizes of endothelial cells were observed on the vesicle area (Figure 2F, white arrows). In some endothelial cells, bright deposits of endothelial cells were observed (Figure 2F, black arrow). The rounded dark areas in the endothelial layer, which were also detected by specular microscopy, were observed more clearly by HRTII-RCM. Inside the dark area, probably protruded hypertrophy of Descemet’s membrane, the monolayer of endothelial cells was observed (Figure 2G, white arrow). The left cornea showed that the margins of the endothelial cells were clear, the shapes of the cells stayed hexagonal, and the sizes of the cells were generally consistent (Figure 3A, B). All images of the Descemet’s membrane and endothelial layer were captured at the center of the cornea.

f3-opth-4-1243: A) In vivo confocal microscopy showed that the left corneal endothelial cell showed the normal appearance. B) The image was captured obliquely and showed no abnormality of keratocytes in the adjacent corneal stroma to the endothelium.

Mentions:
A 15-year-old girl was referred to the Tohoku University General Hospital because of a suspicion of corneal dystrophy. On the right eye, slit-lamp examination revealed a horizontal band-shaped structure which contained small vesicles (Figure 1A, C). The left eye was entirely normal (Figure 1B, D). Her mother’s cornea had no abnormal f indings. Specular microscope (Konan Noncon Specular microscope SP9000; Konan Medical, Inc., Hyogo, Japan) showed that the density of the corneal endothelium and the coefficient of variation were 1331, 1060, 1275 cells/mm2 and 0.36, 0.67, 0.35 at the superior, middle, inferior section, respectively. At the middle area, the shape of the cell was irregular and some parts contained dark areas and bright spots inside the endothelium. In contrast, in the left eye, the density of the central corneal endothelium and coefficient of variation were 2941 cells/mm2 and 0.33, and there were no abnormal findings. The patient was diagnosed as PCV. HRTII-RCM revealed that three different layers were clearly separated in the epithelial layer (superficial, wing, and basal cell layer) on the right eye and suggested that the patient had well-differentiated epithelial cells. In the subbasal nerve plexus layer, the number, bifurcation, and thickness of the nerves showed similar appearance (Figure 2A) to the left eye (Figure 2B), and no inflammatory cells were detected. In the substrate layer, we detected the normal number of keratocytes and neither Langerhans cells nor round leukocytes were detected, suggesting no inflammatory response in the stromal layer. Furthermore, close to the Descemet’s membrane, the cell appearance and the number of the posterior stromal cells look normal (Figure 2C, D). In the Descemet’s membrane layer, an acellular hyporeflective layer (Figure 2E, black arrows) and a hyperreflective linear lesion (Figure 2E, white arrows) were clearly detected (Figure 2E) because of winding the Descemet’s membrane. In the endothelial layer, the various sizes of endothelial cells were observed on the vesicle area (Figure 2F, white arrows). In some endothelial cells, bright deposits of endothelial cells were observed (Figure 2F, black arrow). The rounded dark areas in the endothelial layer, which were also detected by specular microscopy, were observed more clearly by HRTII-RCM. Inside the dark area, probably protruded hypertrophy of Descemet’s membrane, the monolayer of endothelial cells was observed (Figure 2G, white arrow). The left cornea showed that the margins of the endothelial cells were clear, the shapes of the cells stayed hexagonal, and the sizes of the cells were generally consistent (Figure 3A, B). All images of the Descemet’s membrane and endothelial layer were captured at the center of the cornea.

Bottom Line:
At the same time, in vivo confocal microscopy revealed endothelial cells in the rounded dark areas, acellular hyporeflective layers on the Descemet's membrane, and hyperreflective linear lesions.The abnormal findings only existed at the Descemet's membrane and corneal endothelial layer.Previous reports dealing with posterior polymorphous dystrophy (PPMD) examined using in vivo confocal microscopy reported almost the same findings, suggesting that PCV and PPMD may be the same at the microstructural level.

Affiliation:
Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan. ryo-w@oph.med.tohoku.ac.jp

ABSTRACTThe histopathology of posterior corneal vesicles (PCV) has not yet been revealed. A 15-year-old girl, who was diagnosed by slit-lamp microscopy as PCV, was examined using specular microscopy, in vivo confocal microscopy, and anterior segment OCT (optical coherence tomography). Anterior segment OCT showed that the thickness of both corneas was within normal limits. At the same time, in vivo confocal microscopy revealed endothelial cells in the rounded dark areas, acellular hyporeflective layers on the Descemet's membrane, and hyperreflective linear lesions. These findings were not reported previously by slit-lamp and specular microscopy. The abnormal findings only existed at the Descemet's membrane and corneal endothelial layer. Previous reports dealing with posterior polymorphous dystrophy (PPMD) examined using in vivo confocal microscopy reported almost the same findings, suggesting that PCV and PPMD may be the same at the microstructural level.